Extension device



Dec. 17, 1929. N. T. NELSON .1,739,688

l Y EXTENSION DEVICE Filed Nov. 5. 1928 IN1/EN TOR.

A TTORNEYS.

Patented Dec. 17, 1929 UNITED STAT cris NELS T. NELSON, OF ATTLEBORO, MASSACHUSETTS, ASSIGNOR TO J'. F. STURDYS SONS COMPANY, OF ATTLEBORO FALLS, MASSACHUSETTS, A CORPORATION OF MASSA- CEUSETTS EXTENSION DEVICE Application med November 5, 192s. serial No. 317,378.

This invention relates to an extension device for a wrist watch strap; andV has for its Object to provide means by which an increased extension may be had by a folding relation of the different sections and yet a construction which is not of excessive thickness.

A further lobject of the invention is to provide a means for adjustment of the working size of the strap by adjusting the point of the hinging or pivoting of one of the sections to another. i Y

A. still further objectof this invention is to provide sections'which unfold from each side of a section in which they are housed or secured when the device is in its contracted position. Y

With these and other objects in view, the invention consists of certain novel features of construction, as will be more fully described7 and particularly pointed out in the appended claims.

In the accompanying'drawings':

Figfl is a top plan view of the extension device in contracted position.

Fig. 2l is a similar view butfshowing the sections in unfolded or extended position.

. Fig. 3 is a sectional side view of the sections in their unfolded position. t y

Figgi is a perspective lview of the body section.

Fig. 5is a perspective view of the cover section. i i

Fig. 6 is a perspective view of the plate section for hingedly connecting the bodyA and cover sections.

Fig. 7 is a perspective view of the plate section which is hinged to the body section.

Fig. 8 is a perspective view of a section hinged to the section of Fig. 7 and in'turn attached to one end of the strap part.

Fig. 9 is a sectional view showing the parts in folded position.

In wrist straps particularly for wrist watches, extension devices are employed for temporarily lengthening the wrist strap to permit passing of the same over the hand of the wearer without completely detaching and separating any of its parts, and in such a construction it is found desirable to provide an enlargement which will allow the strap to be easily passed over the hand of the wearer or lengthened sufficiently to looselyflit the largest part of the hand over which it must be passed; and in order to provide a foldable Vconstruction having these desirabilities I have provided a larger number of sections to be folded one upon another in a nesting relation than' has been common in practice and have made these sections ofslieet metal'plates to take up the minimum'amiount of space and permit the same to lie closely one upon the other whenin position between the body and cover sections. I have hinged these plates in suchy a manner that the unfolding and enlarging movement is from each side of the centrally located body so that the enlargement is in a measure/equally .distanced from the ends of the strap which attach to the watch. And in this construction, I have provided a means for adjusting one of the plate sections at its point ofpivoting so that an adjustment of the working size of the strap may be pro-v vided which together with the strap adjust-` ment also permits the'centralizing of the de* vice with respect to the ends of the strap; andl the following is a detailed ldescription of the present embodiment of this invention illustrating the preferred means by whichthese advantageous results maybe accomplished.

With reference to the drawings, 10 designates one strap part and 11 the'other strap part which parts are connected'byA a foldable extension' device consisting of a body section 12 and a cover section 13, each of'which is of channel shape having side walls 14 and 15. These two sections are connected by a plate section 16 hingedly attached as at 17 to the body section and provided with a loop 18 at its other end to receive a pivot pin 19 which may selectivelyeng'age any one of a pair ofv ice The other strap part 10 is also provided with a tip 23 which is connected to the body section 12 by means of a pair of plate sections 24 and 25 hinged to each other and to the body and the tip 23 so that the same may be folded one upon theother as illustrated in Fig. 9, between the side wal-ls 14 of the body section 12. The sections 24 and 25 are first folded into the body 1.2 and then the intermediate plate scecti-on 16 is folded over the sec-tion 2Lia-nd 25 and offset at 26 to permit this section to lie snugly against these two folded sec-tions whereby a compact arrangement of the section is provided which may be easily and quickly unfolded into the extended length when desired. i

'Elie hinge' relation between the different sect-ions may be of any suitable form, I having shown here an eye' on one section to be placed in line with a pair of spaced eyes on another section to receive' a pi'ntle or pivot pin to reta-in` the sections in hinge relation.

In order that the sections' may be held in their foldedrelation when the device' is worn as wrist strap' I provide any desirable' means between the cover and body sections to releas-4 ably retain these 'sections together and for illustrative pnrpojses I have shown projo-e: tions or detents 27 extending. outwardly from the side walls 14 of the' body sections to en'- gage in recesses- 28 in the side walls of theV cover section which side walls-'areA resilient to cause a snapping engagement between these parts to retain the sections in their folded p'osition against the accustomed strains due to the enlargement of the wrist by the' muscular movements therein.l

It will be apparentthat the live' sections provided may assume an end to end position' affording an extremely' greatenlargement in' the size of the wrist strap and yet these sections upon being foldable one over the other' perniit a contraction to the wrist encircling size of the wearer with rneans for adjusting this size between the different' sections which aref hince'd together. l

vThev oregoing description is directed solef ly towards the construction illustrated, but I desire itto be understood thatr I reserve the f privilege ofrest-oring to all the mechanical changes to which the device is susceptible, the invention being' defined and limited only by the terms of the appended claims.

I claim:

1. In ,a wrist strap having two strap'r parts an extension' device comprising a body sec-' tion, a cover section, an intermediate plate' pivotally connectingsaid body and cover sec.` tions and foldable therebetween and a plurality of hingedly connected plates hinged'to" one of said sections to told between said sec|- tions andcon-nect one end of one strap part thereto and means for connecting one endof the other strap part to the other section.-

2. In a. wrist strap having two' stra-p parts,-

an extension device comprising a channel body section, a channel cover section, an 1ntermediate section pivotally connecting said body and cover sections and foldable therebetween and a plurality of hingedly connected sections hingedly secured to one of said channel sections and folda-.ble therein to lconnect one end of one strap part thereto,

and-means for connecting one en dof the other str/appart to the other channel section.-`

3. In a wrist strap having two strap-parts, ane-Xtension device comprising a body section, a cover section, an intermediate section pivota'lly connectingsaid body and cover sections and foldable therebetween, means for changing the position of one' ofsa'd pivotal connections, means for connecting one end of one strap part tothe cover section, and means for connecting an end of the other strapl part toy the body section.-

4. In a wrist strap' having. two strap parts, an extension device including'. a body section, a cover section, van intermediate section hinged at one of its ends to' one of said sec-v tions, the other' of said sections having. side walls with a s eries of openings therein, and means for adjistably pivotally connecting the other end of said intermedi-atey section .to the section having side walls,l comprising a pin tol selectively extend into said openings to hingedly connect the other end of said in: termediate scction'to' said side walls.

In 'a wrist strap having twoV strap parts, an extension devicev comprising a body secs tion, a cover section,- an iiltermedi-ate plate pivotally connecting said body and coversecr tions and foldable therebetween and a plurality of hingedly connected plates hinged to one of said sections to fold between said sections and connect one end o'fone strap part thereto, means for connecting one end of the other strap part to the other section, and meansl to releasably secure said body cover sections together to preventL nnfoldng of said plates therebetween.

In testimony whereof I alix mv signa-ture.

NELS T. NELSQN.-

lso 

